In recent years many individuals have turned to their own fitness program of regular jogging. As used herein, jogging is also intended to include running and walking and the words are used interchangeably. Jogging has long been recognized for its therapeutic effects on the body. It purportedly increases cardiopulmonary fitness, helps to lower blood pressure, decreases cholesterol and triglyercides associated with heart disease and reduces weight. Jogging is also one of the easiest exercises to do. It requires no athletic ability and can be done almost any time and any place with a minimum of equipment and without assistance. In more recent times, jogging has also gained acceptance for its recreational value as well and is recognized as a positive factor in promoting psychological well-being.
The popularity of jogging today is well documented by the large numbers of products and literature available to the public. As in many exercise and sporting endeavors, there exists in the prior art a wide variety of devices for aiding those who jog. Many people who run, jog or walk regularly desire to know their progress over time. Therefore, it is desirable to know the accurate distance and speed traveled during an exercise session. This information allows a jogger to monitor his or her progress and accordingly pursue a regular course of exercise designed to enhance performance.
Further, it has become desirable to accurately measure the speed of amateur and professional runners, both in training and during competition. In the prior art, such measurements were made with a stop watch timing the runner over a known distance. Heretofore, it has not been possible to obtain accurate instantaneous speeds of runners or height jumped using the measuring devices currently known in the prior art.
The simplest jogging aids for measuring movements are basic pacing timers such as those disclosed in U.S. Pat. No. 3,540,344 to Veech and U.S. Pat. No. 3,882,480 to Greber. Pacing timers generate a repetitive audio tone signal at selected intervals for pacing the strides of the jogging, where the length of the interval between tones is adjusted to suit the pace of the individual jogger.
There are other running aids known in the prior art such as pedometers as disclosed in U.S. Pat. No. 4,053,755 to Sherrill. These devices usually count the number of steps taken and for a particular stride length, the approximate distance traversed can be determined.
Human speedometers and odometers that measure the speed and distance traveled by a person include devices that utilize ultrasound to measure the distance between each foot such as disclosed in U.S. Pat. No. 4,736,312 to Dassler. Also used is a device that measures the elapsed time of shoe in contact with the ground and converts this to the length of step and speed as disclosed In U.S. Pat. No. 4,578,769 to Frederick.
While pacing timers, pedometers, ultra sound, and elapsed foot-time-distance devices are useful to the runner and walker, they are deficient in several areas. For example, while ultra sound devices can measure the distance between two feet, this is not equivalent to the length of a step or a stride, which is defined as the distance traveled by the same foot from the beginning of a stride till the end of the same stride. For example, the difference between (1) separation between feet, as measured by the ultra sound device, and (2) stride length, is different for each person and will vary for different speeds of running.
Furthermore, devices that employ elapsed-foot-contact-time measurements, have significant errors in measuring stride length. It is known that above a certain speed, stride length begins to increase as speed increases, and the relationship of stride length to speed is not directly proportional, and moreover, is different for each runner. In addition, most of the devices mentioned above require calibration, which may prove to be a difficult task. For example, many of these devices need to be calibrated by the manufacturer or by specially designed equipment.
It is, therefore, a difficult task to determine the correct stride length for an individual runner at various speeds. Thus, pacing timers can provide no more than a constant running pace, and pedometer measurements are only useful as an approximation of distance traversed. Also, ultra sound and elapsed-foot-time-distance devices provide only a rough approximation of actual distance traveled and speed of the person. Also, none of the prior art includes a measurement of height jumped. Running and walking aids known in the prior art are often deficient and cumbersome to use and they often add weight to the runner or walker while providing only marginal utility in terms of the amount of information available and its accuracy.
With the foregoing in mind, the ideal running aid should, therefore: be light in weight; serve a number of useful functions; be inexpensive; provide measurements that are readily available to the user; be reliable and easy to use; and provide accurate measurements of speed, distance traversed, height jumped, and other useful information.